Rotary valve



' 1,614,323 Jan. 11,1927. C'FSMITH ROTARY VALVE Filed Feb. 15. 1923 2. Sheets-Sheet '1 Jan. 11, 1927.

c. F. SMITH ROTARY VALVE 2 Sheets-Sheet 2 Fi led Feb. 15 1923 anpem oz M I Mom 1 Patented Jan. 11, 1927. .j, I 1,614,323

UNITED STATES PATENT orrice.

GARLISLE FORREST SMITH, OF JERSEY CITY, NEW JERSEY, ASSIGNOR TO BOURNON- VILLE ROTARY VALVE MOTOR COMPANY, OF HOBOKEIBT, NEW JERSEY, A CORPORA- TION OF NEW JERSEY.

ROTARY VALVE.

Application filed February 15, 1923. Serial No. 519,176.

The invention relates to rotary valves, and sides which are properly positioned to conparticularly to internal combustion engines nect the cylinder port 7 alternately with having rotary valves controlling the intake the intake and the exhaust at the proper and exhaust of the gases. The object of times. The valve is suitably connected with 55 the invent-ion is to provide certain improvethe crank-shaft to rotate always in one diments upon and within my Patent No. rection, the direction of rotation being in.- 1,t2,705 of January 16, 1923, as hereindicated by the arrow. after more particularly pointed out and The portion 1 1 of the valve chamber above claimed. the fixed bore and opposite the port 7 is 60 In the accompanying drawings forming formed to accommodate a shoe 15, or mobile part hereof: partof the casing, having a segmental under Fig. 1 is a vertical transverse section face substantially conforming to a considerthrough the valve mechanism and the upper able port-i on of the cylindrical surface of the part of one of the cylinders of a multivalve member, it being understood, of course, 65

' cylinder internal combustion engine; that the curvature of the shoe like that of Fig. 2 is a vertical longitudinal section on any bearing is of somewhat greater radius the line 2-2 of Fig. 1; than the rotating member. bove, that is Fig. 3 is a fragmentary sectional elevato say, back of, the shoe, at the top of the tion; and chamber 1 1 is a straight transverse, inclined, 70

Fig. 4: is a vertical longitudinal section rigid way or slide surface 18, against which showing a modification. the shoe is supported through the intermedi- The numeral 1 designates a cylinder block, ary of a slide or wedge. 16 having a sloping and 2 a separate head, the parting or joint back 17 affording an extended sliding surbeing marked 3. The engine will be underface, the slope or taper being transverse to stood as comprising a plurality of cylinders, the shoe and valve and contrary to the diof which the one in the plane of the section rection of rotation of the valve member and is marked a. The head and the adjoining being at a low angle to the line or tangent portion of the cylinder block together form which is at right angles to the central line a casing for a rotary cylindrical valve mempassing through the port 7, the center of the her or plug 5, which extends longitudinally valve member and through or near a rocker over the tops of the cylinders, preferably in joint or point of tilting support, the prestwo or more flexibly jointed sections as is ent preferred form of which will now be familiar. described.

The valve casing contains an incomplete The shoe is provided centrally or in the as cylindrical bore 6, at the bottom of which central line with an opening 10, into which is a port communication 7 to the combustion is inserted, from above, the cylindrical stem chamber 8 of the cylinder, while at oppo- -11 of a ball or hemispherical joint member site sides are an intake manifold and port 19. The slide or wedge member 16 is 12, 11 and an exhaust port and passage 10, 9. formed on its face with a socket correspond- 11:: The cylindrical bore curvature forms seats ing to the'ball, the two forming a universal 60 and 61 at opposite sides of'the cylinder joint between the two members of the movport, between the same and the intake and able structure of the compensating device, exhaust ports, respectively, and a seat 62 which permits the shoe to rock or tilt both at the opposite side of the exhaust port transversely and longitudinally, and in fact from the seat 61, that is to say between the to pivotin any direction, always governed exhaust port and the chamber 14' hereinby and in conformity to the valve member. after referred to. At the intake side the The point of support is substantially central bore is preferably relieved or enlarged above with respect to the ends as well as the sides the intake port and between the same and of the shoe, and proper spaces are left in the 1 the chamber 14 as shown at 6 The valve chamber l lto allow for the complete mobilmember is formed with pocket ports 13 in its of the shoe.

As in my prior patent, the slide or wet ge member and the shoe are pressed in the direction of the taper and contrary to the direction of rotation of the valve member by a spring 20 located in a spring chamber 21 and pressing against the broad end of the wedge. The spring means opposes the circumferential movement of the shoe in one direction and presses the shoe against the valve member and the latter to its seat in the fixed bore, so constantly to hold the valve tight irrespective of expansion and contraction or wear. The slope of the wedge and wedge way is too low to permit the wedge to yield to the force of the explosions or of the compression or the exhaust, the wedge being self-holding in this respect. If, ho vever, the valve tends to stick, owing to expansion, the increased frictional drag of the valve member on the shoe. transmitted through the articulation or toggle, forces the parts slightly against the sgrings and thereby autoniatically relieves the condition. Slight radial movement of the shoe, in or out with respect to the center of the valve, is thus obtained by virtue of true circumferential movement in one direction or the other. The springs are of such strength as to resist normal frictional drag sufliciently to secure the desired tightness.

By virtue of the capacity of the shoe for longitudinal tilting, added to its capacity for transverse tilting, it is insured that the shoe will conform and bear evenly upon the valve member throughout the length of the shoe, both initially and during all movements either of the valve member or of the shoe. In rotary valves for internal combustion engines the amount of permissible deviation from absolute accuracy in the bearing surfaces is extremely small, owing to the great heat and the exposure of the valve member to the combustion gases on the one hand and the necessity of maintaining a good seal on the other hand. It results that there is a range of a few thousandths of an inch within which there can be satisfactory operation, variations above one limit causing excessive loss of power and variations below the other limit resulting in destructive binding and cutting.

There are three sets of bearing surfaces one between the valve member and the bottom of the casino. another between the top of the valve member and the shoe, and the third between the slide or wedge and the slide surface of the casing. All of these are theoretically parallel in the longitudinal direction, but slight inaccuracies'of manufacture are inevitable, and even with great care very minute inaccuracies in the several places are likely to mount up to a total which, though small actually. is sufficient to derange the operation of the valve. The present construction overcomes this difficulty, renders manufacture less exacting,

and secures the further important advantage of rendering the shoes interchangeable.

Other forms of the double or universal rocker may be employed, but the construction illustrated possesses special advantage in case of manufacture. llurtherm-ore, as illustrated in Fig. 3, it permits of the coin pensating device being restored to full operativeness after the various parts have worn to such an extent that the wear can no longer be taken care of auton'iatically. At such time all that is necessary to do is to remove the shoe or shoes, take the ball member 19 out of the shoe, and replace it with one or more washer-lilac shims 4-2 between its shoulder and the back of the shoe, thus varying the spacing between the shoe and its movable backing member 16.

As seen in Figs. 2 and 1, each shoe is of limited longitudinal extent. As disclosed in the patent to Eugene M. Bournonville No. lei-72,113, dated October 30, 1923, there are preferably two or a plurality of the shoes for each section of the valve member, so that the shoes can have slight independent or relative movement on different portions of the valve section. Fig. 2 illustrates a construction in which there is a. separate spring-pressed wedge or slide for each shoe. Similar functioning can be secured with greater advantage in manufacturing by combining-two or more shoes with a common wedge or slide 16 jointed to the shoes by separate ball joints. In this case, if one shoe mo es circumferentially of the valve member somewhat farther than the other owing to a difference in conditions at the two regions, the common wedge will skew slightly on its slideway.

Returning to the preferred construction of the bearing forthe valve, it will be seen that the total fixed bearing is confined to an are which includes'the seats 60, 61 and 62 and the cylinder and exhaust ports 7 and 10, this arc being subtended by a chord passing diagonally to include these regions and be ing materially less than 180. The valve member does not touch at the enlarged region 6 of the casing extending between the intake 12 and the compensating device chamber 14, the entire additional bearing for the valve member being provided by the yielding shoe 15. I find that a valve member left free in this manner is yet kept perfectly seated, so as to avoid any leakage or straying of intake and exhaust gases that would interfere with the operation of the engine or impair its efficiency. However great the expansion of the valve member due to heating by the hot gases, it can not seize or become bound in the bearing, and conse quently the clearance,'that is to say the difference between the radii of the valve member and 0f the fixed bearing seats can be very ill) slight, which is in turn favorable for good seating.

Various other modifications and changes in form and detail may be made without departing from the invention.

lVhat I claim as new is:

1. An internal combustion engine valve having a rotary valve member and a casing communicating with the combustion chamber, a compensating device comprising a shoe bearing on the curved surface of the valve member and movable circumferentially thereon in response to variations in the drag oi the valve member which is opposed by a spring, and backing means for the shoe causing the shoe to recede from or approach the center of the valve member according as the shoe moves circum't'erenl ially in one direction or the other, the shoe being completely supported by the backing means at a region central with respect to its sides and ends so as to be free to tilt both transversely and longitudinally while performing its compensating functions.

2. In a rotary valve having a rotary valve member and a casing, an automatic compensating device comprising a two-part movable structure having its parts connected by a universal oint, one of the parts being a shoe which is movable circumierentially on the valve member while the other part executes a different movement to cause simultaneous slight recession or approach of the shoe.

3. In a rotary valve, a valve member, a casing having a guide, a slide movable on said guide transversely of the valve member, a circum'ferentially movable shoe bearing on the valve member, and a ball joint between said slide and shoe.

4-. In an internal combustion engine, a rotary valve member, a valve casing having a port communicating with the combustion chamber and a transversely inclined guide opposite said port, a spring-pressed wedge or slide movable on said guide, a shoe bearing on the valve member, and a universal rocker joint between said wedge and shoe.

5. In a rotary valve having a rotary valve member and a casing, an automatic compensating device comprising a backing guide or ing device comprising a transversely movable slidable member and a circumterentially movable shoe member, one of said members having a central opening and the other a ball. socket, and a ball engaging said socket and having a stem inserted in said opening.

7. In a rotary valve having a valve member, and a casing, an automatic compensating device comprising a shoe movable circumferentially of the valve member, and a spring-pressed backing member guided in the valve casing, and a ball engaging a socket in one of said members and having a stem set into the other member.

8. A rotary valve of the kind described, comprising a casing having a port to communicate with a cylinder, intake and exhaust ports on either hand of such cylinder port, and a chamber at the far side opposite from the cylinder port, a rotary VZLlVL member adapted to connect the cylinder port with the exhaustport and then with the intake port, and an automatic compensating device in said chamber having a shoe bearing upon the valve member, said casing being formed with fixed arcuate bearing seats at opposite sides of the cylinder port, that is to say between the oylinder port and the intake and exhaust ports respectively, and also at the side of the exhaust port away from the cylinder port, that is to say between the exhaust port and the compensating device chamber, the interior of the casing between the intake port and the compensating device chamber being enlarged, the total are of fixed bearing being subtended by a chord passing diagonally to include said seats and the cylinder and exhaust ports and being less than 180.

OARLISLE FORREST SMITH. 

